Are there any examples of how to use GCD from iOS ...

# multiplatform

[Trey]

Are there any examples of how to use GCD from iOS via Kotlin? I'm trying to work out a few issues and that would be helpful.

[mbonnin]

We're using it here: https://github.com/apollographql/apollo-kotlin/blob/f38bbedee78c2fabc9cdae0d680036a24f7048ff/apollo-runtime/src/appleMain/kotlin/com/apollographql/apollo3/internal/dispatchers.kt#L48

[Trey]

Thanks, that's helpful. I'm trying to create a serial queue and I'm trying to work out how to access DISPATCH_QUEUE_SERIAL. I didn't see any place that your code does that. Did I miss it? Looks like it just uses system queues.

[mbonnin]

Looks like DISPATCH_QUEUE_SERIAL is just null: https://opensource.apple.com/source/libdispatch/libdispatch-685/dispatch/queue.h.auto.html

[mbonnin]

So you might make it work by passing just "null"

[mbonnin]

dispatch_queue_create("myqueue", null)

[mbonnin]

That doesn't solve the more general issue though 😅

[mbonnin]

I would try something in the likes of this in the general case:

dispatch_queue_create("myqueue", DISPATCH_QUEUE_SERIAL!!.reinterpret<dispatch_queue_attr_tVar>().pointed.value)

[mbonnin]

Well, actually more like

dispatch_queue_create("myqueue", DISPATCH_QUEUE_SERIAL?.reinterpret<dispatch_queue_attr_tVar>()?.pointed?.value)

[mbonnin]

(but I haven't tested any of this)

[Trey]

Thanks for the advice. I'll give that a try.